This heatsink with ID2.0mm neck solves thermal creep problems. It would be better to apply some thermal paste to properly fit the CR10 heatsink. Please make sure there is no gap between the heatsink and the thermal breaker These thermal breaks are made of TC4 titanium alloy to provide excellent thermal insulation between the heater and the cooling block. Titanium is an extremely strong material and offers almost 3 times lower thermal conductivity than stainless steel, creating a more defined cast. There is an OD7mm sidewall between the handle and the threaded part, this which can fix the heat breaker and the nozzle more stable. Side wall with two cutouts convenient to use a 6mm wrench to screw the heat breaker out of the heater block. Used for Creality CR10, S4 S5, CR10S, Ender 3 Series, ender-3 Pro, 3D printer CS3 Hotend; if you want to use this heat cutter with other printers, please check our drawings before ordering. It is all kind of metal, you can use it for super high temperature printing.